PURPOSE: A structure of an alignment mark pattern is provided to increase a contact density between a polishing pad and a center portion of an alignment mark by forming a mosaic pattern on a groove of an alignment mark. CONSTITUTION: A tungsten plug for internal connection of a semiconductor device is formed on a contact hole by using a CMP(Chemical Mechanical Polishing) process. The contact hole is formed on an available region of an insulating layer. A metal layer is deposited thereon. A mask alignment mark is formed on a non-available region of the insulating layer in order to align a mask. The mask alignment mark is formed with a multitude of line pattern. A mosaic pattern is formed on grooves of each line pattern.
